Rock-drilling machine



(No M CHINE. No. 510,517. Patented Dec. 12, 1893 odel.) v 3 She tttttttt 1. Y

J. A, PEARSALL & O. M.- WALKER.

ROCK DRILLING MA (No Model.) 1 s SheetsShet 2;

A. PEARSALL G. M WALKER.

ROCK DRILLING MACHINE,

No. 51-0517. Patented Dec. 12, 18 93.

J PeafaaloQ IHI NAYIONAL LITNOBRAFHING couPANv.

(No Model.) 3 SheetsSheet 3. J. A. PEA'RSALL & .0 M. WALKER. ROCK DRILLING MACHINE Patent ed Dec. 12, 1893.

mvm-bow JA.FearsaZ&

THE NATIONAL LITNOGRAFHINR com-ANY.

WASHINGTON. n. o.

- 3o guide piece.

UNITED STATES PATENT OFFICE.

JAMES ALFRED PEARSALL AND OASSIUS MARSHALL WALKER, OF DENVER, ASSIGNORS TO THE ROCKY MOUNTAIN DRILL COMPANY, OF PUEBLO,

COLORADO.

RROCKQDIRILLING MACHINE.

SPECIFICATION forming part of Letters Patent No. 510,517, dated December 12, 1893.

Application filed November 25, 1891- Serial No. 413,152. (No model.)

T at whom it may concern.-

Be it known that we, JAMES ALFRED PEAR- SALL and CASSIUS MARSHALL WALKER, citizens of the United States, residing at Denver, in the county of Arapahoe and State of Colorado, have invented certain Improvements in Rock-Drilling Machines, of which the following is a specification.

The object of our invention is to produce [0 improved mechanism for operating drills 20 a side elevation of our machine. Fig. 2 is a central vertical longitudinal section of Fig. 1, showing some of the driving parts in elevation. Fig. 3 is a longitudinal section taken on the line 3, 3, of Fig. 2. Fig. 4 is a plan 25-view of the hammer and guide-piece, de-

tached. Fig. 5 is a-side elevation of valves and stem. Fig. 6. is a similar view, taken at right angles to that shown in Fig. 5. .Fig. 7 is a vertical cross section of the hammer and Figs. 8 and 9 illustrate the relative positions of the two valves in one operation of the machine; and Figs. 10 and 11 illustrate the same in their other positions.

Referring to thewfigures on the drawings, 1

35 indicates the shell of our machine, which is preferably made of cast metal. It is adapted to be carried upon a suitable frame, as for example a tripod, and to be advanced by any suitable means in the direction of its out.

' is carried the main piston cylinder 3 and the valve piston cylinders 4 and 5. The valvepiston cylinders are connected by ports 6 and 7,and 8 and 9 respectively, which communi- 45 cate with an intermediate'valve seat 10, from which, at right angles, lead the ports 11 and 12, respectively communicating with it, opposite the ports 6 and 7 and 8 and 9. The valve- 2 indicates the head of the shell, in which carries valves 14 and 15 adapted to control the ports 6, 7, and 11 and 8, 9, and 12 respectively. The lower end of the valvestem sets upon a bench 16 in the shell, where a pointed screw 17 is provided as a bearing, and by which the stem may be moved toward the valve-seat to compensate for wear of the parts.

The valve 14 is preferably provided with ports 18 and 19, and a medial wall 20. The valve 15'is provided with a single recess or port 21. The valves are so arranged with respect to each other that by the partial rotation of the valve-stem they may control each set of cylinder ports, as shown in Figs. 8,, 9, 10, and 11 respectively.

22 indicates a vent communicating with the interior of the cylinder 5.

23 indicates a supply pipe communicating with a source of steam or compressed air, not illustrated; and 24 indicates a branch supply-pipe communicating with the pipe 23, and with the cylinders4 and 5 respectively through connections 25 and 26.

27 indicates one of the valve-pistons and 28 the other.

29 indicates a stem of thefpiston 2'7, and 30 that of vthe piston 28. These stems pass through bushings 31 and 32, respectively, and are pivotally connected, as by heads 33 and 34 respectively to pitmen 35 and 36, which are pivotally connected to dogs 37 and 38mspec'tivelyfwhich are carried upon a pivoted shaft 39 journaled in the side of the shell.

40 indicates trip-levers secured to the dog 38. These trip-levers extend in opposite directions, and are designed alternately to impinge against fingers 42 and 43, respectively secured, as by bosses 44 and 45, to the valvestem 13. The oflfice of these trip levers is to impart the required rotatory movement to the valves 14 and 15 to control the cylinder ports in the manner above suggested.

46 indicates a main piston.

47 indicates the main piston rod passing seat is preferably slightly tapered toreceive a 5o correspondingly tapered valve-stem 13 which 51 indicates an aperture in the end of the sist in removing the drill when required.

The holder is yieldingly urged toward the hammer as by a spiral spring 58, seated at one end in the end of the shell, and bearing at the other end against a collar 59 secured to the holder.

indicates an obliquely channeled collar,

with which an oblique rib 61 from the guidepiece 50 is adapted to engagein each reciprocation of the guide-piece. By this arrangement the rib imparts a slight rotatory movement with each reciprocation of the guidepiece. Upon the next movement ofthe g'uidepiece, the rib engages with the next channel and imparts an additional rotatory move-j Each reciprocation of the hammer,

ment. therefore, sets the drill anew.

62 indicates a tubular cover communicating'with a recessed carrier upon the outer end of a recessed housing 63 aroundthe drill,

and near its cutting end the diameter of the; head of thedrill should be somewhat greater than the tubularcover, so that the hole formed by the drill will be larger than the'cover, as

indicated by dotted lines in Figs. 2 and 3.

64 indicates a branch pipe communicating with the supply pipe 23, and with the recess} in the housing 63.

into the pipe 24, or the pipe 64, at will.

admitted into the cylinder 4 will pass through the port 8 into the valve-seat 10, and thence through the port 12 into thecylinder3l The piston 46 will then be driven toward the head of the cylinder carrying the hammer 49 with it. The point of the dog 37 will travel along the way 53 until it reaches the beveled end 54, when it will be released. This will occur just as piston 46 reaches the limit of its travel. Upon the release of the dog 37 the steam in the cylinder 5, above the piston 28, will drive the piston-rod 30 a short distance, sufi'icient to operate the trip-lever 40 and force it against the finger 43 ,thereby rotating the valves 14 and 15' and reversing them to the relative positions shownin Figs. 10 and l1,respectively. Thereupon live steam from the cylinder 4, through the ports 6 and 11,enters the cylinder 3 and drives the piston 46 in the opposite I The dead steam exhausts through direction.

the ports 12 and 9 into the cylinder 5 and out through the aperture 22. It will be observed in this connection that in the movement of the piston previously described, the exhausts pass through the ports 11 and 7 into the cylder 5 and thence out through the opening 22. As the hammer driven by its piston 46 descends, it engages upon its ways 52 and 53 the dogs 37 and 38. The dog 37 is retained in its way, butthe dog 38, slipping away from the hammer,isreleased, audthe piston 27 is operated by the steam in the cylinder 4 to bring the trip-lever 41 against the finger 43, and restores the valves 14 and 15 to the positions shown in Figs. 8 and 9 respectively. Thereupon the operation is repeated as before.

The operations above described are performed with great rapidity, and with each complete reciprocation thetool-holder is given a sharp quick blow, and is followed by the hammer, under pressure of steam, long enough to prevent its rebound. The holder, therefore,.presents a rigid resistance to the stroke of the hammer each time, and the tool is driven evenly and regularly. When atool becomes clogged with cuttings the operation of the hammer may be interrupted and the steam or air forced through the pipefietinto the cover 62. In this manner a blast of air is driven into the bottom of the hole and the debris .is blown out around the cover.

While .we haveillustrated anddescribed a particular form of embodiment of our invention, we do not wish tolimit ourselves to the details of construction; but desire to modify and vary them at will within thescopeof our 1 invention. indicates an ordinary three-way cock, adapted to direct the supply from the pipe 23 Whatwe claim is:- 1. The combination with a cylinder and pisston therein, andapair of valve piston cylinln operation, suppose the valve-operating piston and the main piston to be in relative. positions, shown in Figs. 2 and 3, and steam to be admitted into the pipe 24. The valves 14 and 15 will then be in the relative positions shown in Figs. .8 and 9 respectively. Steam ders, of a valve adapted to admit the steam alternately above. and below said piston from one of the valve pistoncylinders and to permit its exhaust into the other, substantially as specified.

2. Thecombination with a cylinder and pis* ton, and a valve, of a pair of valve piston cylinders and valve pistons therein adapted to control the movement of the valve to admit the steam from one of the valve piston cylin ders alternately above and below the piston and permit the exhaust into the other, and mechanism operatively connectingthe valve pisitons with the valve, substantially as speci- 3. The combination with a mainpiston and cylinder, a controlling valve and a pair of inders all arranged longitudinally with re-- spect to each other, said shell having ports communicating each end, respectively, of the main cylinder with the adjacent ends of the other cylinders, said valve being adapted to control the supply and exhaust to and from the main cylinder through said ports, substantially asspecified.

6. The combination with a shell and main piston, of a controlling valve separate cylinders, supply pipes connected thereto, pistons in said cylinders, and a trip lever operatively connected to said pistons and adapted to actuate the Valve, substantially in the manner and for the purpose specified.

7. The combination with a shell, piston, rod, and hammer, of a valve for controlling the supply of steam to the piston, a trip-lever under constant pressure for operating the valve, and a dog controlled by the movement of the hammer for actuating the trip-lever, substantially as set forth.

8. The combination with a shell, piston, rod, and hammer, of a valve adapted to control the supply of steam to the piston, pivoted dogs and trip levers, ways in the hammer controlling the dogs, and pistons adapted to actuate the dogs when released from the hammer to cause the trip levers to intermittently actuate the valve, substantially in the manner and for the purpose specified.

9. The combination with a shell and reciprocatory hammer, of a guide-piece and oblique rib, a tool-holder having an obliquely channeled collar adapted to engage with the oblique rib, substantially in the manner and for the purpose specified.

10. In a rock drill, the combination with a tool-holder and tool, of a tubular cover surrounding the tool, and mechanism for supplying a blastwithin the cover around the tool, substantially in the manner and for the purpose specified.

JAMES ALFRED PEARSALL. OASSIUS MARSHALL WALKER.

Witnesses:

MARCUS AURELIUS HAINES, JEROME F. 000KB 

